diff --git a/Cargo.lock b/Cargo.lock
index 7396fe3..55771fe 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -105,6 +105,7 @@ dependencies = [
  "flatbuffers 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "flatc-rust 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "nom 5.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "smallvec 0.6.10 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
diff --git a/Cargo.toml b/Cargo.toml
index e1fd6fc..f2eef64 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -9,6 +9,7 @@ capnp = "0.10.1"
 clap = "2.33.0"
 flatbuffers = "0.6.0"
 nom = "5.0.0"
+smallvec = "0.6.10"
 
 [build-dependencies]
 capnpc = "0.10"
diff --git a/build.rs b/build.rs
index d231930..42af504 100644
--- a/build.rs
+++ b/build.rs
@@ -7,11 +7,13 @@ fn main() {
         .src_prefix("")
         .file("marketdata.capnp")
         .output_path("src/")
-        .run().expect("Unable to compile capnpc");
+        .run()
+        .expect("Unable to compile capnpc");
 
     flatc_rust::run(flatc_rust::Args {
         inputs: &[Path::new("marketdata.fbs")],
         out_dir: Path::new("src/"),
         ..Default::default()
-    }).expect("Unable to compile flatc");
-}
\ No newline at end of file
+    })
+        .expect("Unable to compile flatc");
+}
diff --git a/src/iex.rs b/src/iex.rs
new file mode 100644
index 0000000..2259ce0
--- /dev/null
+++ b/src/iex.rs
@@ -0,0 +1,418 @@
+use std::convert::TryInto;
+
+use nom::{bytes::complete::take, IResult, number::complete::*, sequence::tuple};
+
+#[derive(Debug)]
+struct IexPayload {
+    version: u8,
+    _reserved: u8,
+    proto_id: u16,
+    channel_id: u32,
+    session_id: u32,
+    payload_len: u16,
+    msg_count: u16,
+    stream_offset: u64,
+    first_seq_no: u64,
+    send_time: i64,
+    messages: smallvec::SmallVec<[IexMessage; 8]>,
+}
+
+#[derive(Debug)]
+enum IexMessage {
+    SystemEvent(SystemEvent),
+    SecurityDirectory(SecurityDirectory),
+    TradingStatus(TradingStatus),
+    OperationalHaltStatus(OperationalHaltStatus),
+    ShortSalePriceTest(ShortSalePriceTest),
+    SecurityEvent(SecurityEvent),
+    PriceLevelUpdate(PriceLevelUpdate),
+    TradeReport(TradeReport),
+    OfficialPrice(OfficialPrice),
+    TradeBreak(TradeBreak),
+    AuctionInformation(AuctionInformation),
+}
+
+macro_rules! parse_msg {
+    ($input:ident, $msg_type:ident) => {{
+        let (rem, msg) = $msg_type::parse($input)?;
+        Ok((rem, IexMessage::$msg_type(msg)))
+    }};
+}
+
+impl IexMessage {
+    // TODO: Benchmark a version where we cast a packed struct instead of parsing
+    fn parse(input: &[u8]) -> IResult<&[u8], IexMessage> {
+        let msg_type = input[0];
+        match msg_type {
+            0x53 => parse_msg!(input, SystemEvent),
+            0x44 => parse_msg!(input, SecurityDirectory),
+            0x48 => parse_msg!(input, TradingStatus),
+            0x4f => parse_msg!(input, OperationalHaltStatus),
+            0x50 => parse_msg!(input, ShortSalePriceTest),
+            0x45 => parse_msg!(input, SecurityEvent),
+            // Why the "match multiple" looks like bitwise-OR is beyond me.
+            0x38 | 0x35 => parse_msg!(input, PriceLevelUpdate),
+            0x54 => parse_msg!(input, TradeReport),
+            0x58 => parse_msg!(input, OfficialPrice),
+            0x42 => parse_msg!(input, TradeBreak),
+            _ => panic!("Unrecognized message type"),
+        }
+    }
+}
+
+#[derive(Debug)]
+struct SystemEvent {
+    msg_type: u8,
+    system_event: u8,
+    timestamp: i64,
+}
+
+impl SystemEvent {
+    fn parse(input: &[u8]) -> IResult<&[u8], SystemEvent> {
+        let (rem, (msg_type, system_event, timestamp)) = tuple((le_u8, le_u8, le_i64))(input)?;
+
+        Ok((
+            rem,
+            SystemEvent {
+                msg_type,
+                system_event,
+                timestamp,
+            },
+        ))
+    }
+}
+
+#[derive(Debug)]
+struct SecurityDirectory {
+    msg_type: u8,
+    flags: u8,
+    timestamp: i64,
+    symbol: [u8; 8],
+    lot_size: u32,
+    previous_closing: u64,
+    luld_tier: u8,
+}
+
+impl SecurityDirectory {
+    fn parse(input: &[u8]) -> IResult<&[u8], SecurityDirectory> {
+        let (rem, (msg_type, flags, timestamp, symbol, lot_size, previous_closing, luld_tier)) =
+            tuple((le_u8, le_u8, le_i64, take(8usize), le_u32, le_u64, le_u8))(input)?;
+
+        Ok((
+            rem,
+            SecurityDirectory {
+                msg_type,
+                flags,
+                timestamp,
+                symbol: symbol.try_into().unwrap(),
+                lot_size,
+                previous_closing,
+                luld_tier,
+            },
+        ))
+    }
+}
+
+#[derive(Debug)]
+struct TradingStatus {
+    msg_type: u8,
+    trading_status: u8,
+    timestamp: i64,
+    symbol: [u8; 8],
+    reason: [u8; 4],
+}
+
+impl TradingStatus {
+    fn parse(input: &[u8]) -> IResult<&[u8], TradingStatus> {
+        let (rem, (msg_type, trading_status, timestamp, symbol, reason)) =
+            tuple((le_u8, le_u8, le_i64, take(8usize), take(4usize)))(input)?;
+
+        Ok((
+            rem,
+            TradingStatus {
+                msg_type,
+                trading_status,
+                timestamp,
+                symbol: symbol.try_into().unwrap(),
+                reason: reason.try_into().unwrap(),
+            },
+        ))
+    }
+}
+
+#[derive(Debug)]
+struct OperationalHaltStatus {
+    msg_type: u8,
+    halt_status: u8,
+    timestamp: i64,
+    symbol: [u8; 8],
+}
+
+impl OperationalHaltStatus {
+    fn parse(input: &[u8]) -> IResult<&[u8], OperationalHaltStatus> {
+        let (rem, (msg_type, halt_status, timestamp, symbol)) =
+            tuple((le_u8, le_u8, le_i64, take(8usize)))(input)?;
+
+        Ok((
+            rem,
+            OperationalHaltStatus {
+                msg_type,
+                halt_status,
+                timestamp,
+                symbol: symbol.try_into().unwrap(),
+            },
+        ))
+    }
+}
+
+#[derive(Debug)]
+struct ShortSalePriceTest {
+    msg_type: u8,
+    sspt_status: u8,
+    timestamp: i64,
+    symbol: [u8; 8],
+    detail: u8,
+}
+
+impl ShortSalePriceTest {
+    fn parse(input: &[u8]) -> IResult<&[u8], ShortSalePriceTest> {
+        let (rem, (msg_type, sspt_status, timestamp, symbol, detail)) =
+            tuple((le_u8, le_u8, le_i64, take(8usize), le_u8))(input)?;
+
+        Ok((
+            rem,
+            ShortSalePriceTest {
+                msg_type,
+                sspt_status,
+                timestamp,
+                symbol: symbol.try_into().unwrap(),
+                detail,
+            },
+        ))
+    }
+}
+
+#[derive(Debug)]
+struct SecurityEvent {
+    msg_type: u8,
+    security_event: u8,
+    timestamp: i64,
+    symbol: [u8; 8],
+}
+
+impl SecurityEvent {
+    fn parse(input: &[u8]) -> IResult<&[u8], SecurityEvent> {
+        let (rem, (msg_type, security_event, timestamp, symbol)) =
+            tuple((le_u8, le_u8, le_i64, take(8usize)))(input)?;
+
+        Ok((
+            rem,
+            SecurityEvent {
+                msg_type,
+                security_event,
+                timestamp,
+                symbol: symbol.try_into().unwrap(),
+            },
+        ))
+    }
+}
+
+#[derive(Debug)]
+struct PriceLevelUpdate {
+    msg_type: u8,
+    event_flags: u8,
+    timestamp: i64,
+    symbol: [u8; 8],
+    size: u32,
+    price: u64,
+}
+
+impl PriceLevelUpdate {
+    fn parse(input: &[u8]) -> IResult<&[u8], PriceLevelUpdate> {
+        let (rem, (msg_type, event_flags, timestamp, symbol, size, price)) =
+            tuple((le_u8, le_u8, le_i64, take(8usize), le_u32, le_u64))(input)?;
+
+        Ok((
+            rem,
+            PriceLevelUpdate {
+                msg_type,
+                event_flags,
+                timestamp,
+                symbol: symbol.try_into().unwrap(),
+                size,
+                price,
+            },
+        ))
+    }
+}
+
+#[derive(Debug)]
+struct TradeReport {
+    msg_type: u8,
+    sale_condition: u8,
+    timestamp: i64,
+    symbol: [u8; 8],
+    size: u32,
+    price: u64,
+    trade_id: u64,
+}
+
+impl TradeReport {
+    fn parse(input: &[u8]) -> IResult<&[u8], TradeReport> {
+        let (rem, (msg_type, sale_condition, timestamp, symbol, size, price, trade_id)) =
+            tuple((le_u8, le_u8, le_i64, take(8usize), le_u32, le_u64, le_u64))(input)?;
+
+        Ok((
+            rem,
+            TradeReport {
+                msg_type,
+                sale_condition,
+                timestamp,
+                symbol: symbol.try_into().unwrap(),
+                size,
+                price,
+                trade_id,
+            },
+        ))
+    }
+}
+
+#[derive(Debug)]
+struct OfficialPrice {
+    msg_type: u8,
+    price_type: u8,
+    timestamp: i64,
+    symbol: [u8; 8],
+    official_price: u64,
+}
+
+impl OfficialPrice {
+    fn parse(input: &[u8]) -> IResult<&[u8], OfficialPrice> {
+        let (rem, (msg_type, price_type, timestamp, symbol, official_price)) =
+            tuple((le_u8, le_u8, le_i64, take(8usize), le_u64))(input)?;
+
+        Ok((
+            rem,
+            OfficialPrice {
+                msg_type,
+                price_type,
+                timestamp,
+                symbol: symbol.try_into().unwrap(),
+                official_price,
+            },
+        ))
+    }
+}
+
+#[derive(Debug)]
+struct TradeBreak {
+    msg_type: u8,
+    sale_condition: u8,
+    timestamp: i64,
+    symbol: [u8; 8],
+    size: u32,
+    price: u64,
+    trade_id: u64,
+}
+
+impl TradeBreak {
+    fn parse(input: &[u8]) -> IResult<&[u8], TradeBreak> {
+        let (rem, (msg_type, sale_condition, timestamp, symbol, size, price, trade_id)) =
+            tuple((le_u8, le_u8, le_i64, take(8usize), le_u32, le_u64, le_u64))(input)?;
+
+        Ok((
+            rem,
+            TradeBreak {
+                msg_type,
+                sale_condition,
+                timestamp,
+                symbol: symbol.try_into().unwrap(),
+                size,
+                price,
+                trade_id,
+            },
+        ))
+    }
+}
+
+#[derive(Debug)]
+struct AuctionInformation {
+    msg_type: u8,
+    auction_type: u8,
+    timestamp: i64,
+    symbol: [u8; 8],
+    paired_shares: u32,
+    reference_price: u64,
+    indicative_clearing_price: u64,
+    imbalance_shares: u32,
+    imbalance_side: u8,
+    extension_number: u8,
+    scheduled_auction: u32,
+    auction_book_clearing_price: u64,
+    collar_reference_price: u64,
+    lower_auction_collar: u64,
+    upper_auction_collar: u64,
+}
+
+impl AuctionInformation {
+    fn parse(input: &[u8]) -> IResult<&[u8], AuctionInformation> {
+        // Dear Lord, why?
+        let (
+            rem,
+            (
+                msg_type,
+                auction_type,
+                timestamp,
+                symbol,
+                paired_shares,
+                reference_price,
+                indicative_clearing_price,
+                imbalance_shares,
+                imbalance_side,
+                extension_number,
+                scheduled_auction,
+                auction_book_clearing_price,
+                collar_reference_price,
+                lower_auction_collar,
+                upper_auction_collar,
+            ),
+        ) = tuple((
+            le_u8,
+            le_u8,
+            le_i64,
+            take(8usize),
+            le_u32,
+            le_u64,
+            le_u64,
+            le_u32,
+            le_u8,
+            le_u8,
+            le_u32,
+            le_u64,
+            le_u64,
+            le_u64,
+            le_u64,
+        ))(input)?;
+
+        Ok((
+            rem,
+            AuctionInformation {
+                msg_type,
+                auction_type,
+                timestamp,
+                symbol: symbol.try_into().unwrap(),
+                paired_shares,
+                reference_price,
+                indicative_clearing_price,
+                imbalance_shares,
+                imbalance_side,
+                extension_number,
+                scheduled_auction,
+                auction_book_clearing_price,
+                collar_reference_price,
+                lower_auction_collar,
+                upper_auction_collar,
+            },
+        ))
+    }
+}
diff --git a/src/main.rs b/src/main.rs
index d9c4aed..ae20f9e 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -3,8 +3,9 @@ use std::io::Read;
 use std::path::Path;
 
 use clap::{App, Arg};
+use nom::sequence::tuple;
 
-use pcap_ng::Block;
+use parsers::Block;
 
 // Cap'n'Proto and Flatbuffers typically ask that you generate code on the fly to match
 // the schemas. For purposes of auto-complete and easy browsing in the repository,
@@ -13,7 +14,8 @@ pub mod marketdata_capnp;
 #[allow(unused_imports)]
 pub mod marketdata_generated; // Flatbuffers
 
-mod pcap_ng;
+mod iex;
+mod parsers;
 
 fn main() {
     let matches = App::new("Marketdata Shootout")
@@ -34,7 +36,7 @@ fn main() {
     file.read_to_end(&mut buf).expect(&format!("Unable to read file={}", path.display()));
 
     let mut rem = &buf[..];
-    while let Ok((unparsed, block)) = pcap_ng::read_block(rem) {
+    while let Ok((unparsed, block)) = parsers::read_block(rem) {
         let offset = (unparsed.as_ptr() as usize) - (buf.as_ptr() as usize);
         rem = unparsed;
         match block {
diff --git a/src/pcap_ng.rs b/src/parsers.rs
similarity index 51%
rename from src/pcap_ng.rs
rename to src/parsers.rs
index 5d75520..7896631 100644
--- a/src/pcap_ng.rs
+++ b/src/parsers.rs
@@ -1,16 +1,11 @@
+use std::convert::TryInto;
 use std::mem::size_of;
 
 use nom::{
-    branch::alt,
-    bytes::complete::tag,
-    bytes::complete::take,
-    IResult,
-    number::complete::*,
+    branch::alt, bytes::complete::tag, bytes::complete::take, IResult, number::complete::*,
     sequence::tuple,
 };
 
-use crate::pcap_ng::Block::EnhancedPacket;
-
 pub enum Block<'a> {
     SectionHeader(SectionHeaderBlock),
     InterfaceDescription(InterfaceDescriptionBlock),
@@ -21,49 +16,43 @@ pub fn read_block(input: &[u8]) -> IResult<&[u8], Block> {
     alt((
         section_header_block,
         interface_description_block,
-        enhanced_packet_block
+        enhanced_packet_block,
     ))(input)
 }
 
 #[derive(Debug)]
 pub struct SectionHeaderBlock {
-    block_len: u32
+    block_len: u32,
 }
 
 const SECTION_HEADER: [u8; 4] = [0x0a, 0x0d, 0x0d, 0x0a];
 
 pub fn section_header_block(input: &[u8]) -> IResult<&[u8], Block> {
     let header_len = 12;
-    let (rem, (_, block_len, _)) = tuple((
-        tag(SECTION_HEADER),
-        le_u32,
-        tag([0x4d, 0x3c, 0x2b, 0x1a])
-    ))(input)?;
+    let (rem, (_, block_len, _)) =
+        tuple((tag(SECTION_HEADER), le_u32, tag([0x4d, 0x3c, 0x2b, 0x1a])))(input)?;
 
     take(block_len - header_len)(rem)
-        .map(|i| (i.0, Block::SectionHeader(SectionHeaderBlock {
-            block_len
-        })))
+        .map(|i| (i.0, Block::SectionHeader(SectionHeaderBlock { block_len })))
 }
 
 #[derive(Debug)]
 pub struct InterfaceDescriptionBlock {
-    block_len: u32
+    block_len: u32,
 }
 
 const INTERFACE_DESCRIPTION: [u8; 4] = [0x01, 0x00, 0x00, 0x00];
 
 pub fn interface_description_block(input: &[u8]) -> IResult<&[u8], Block> {
     let header_len = 8;
-    let (rem, (_, block_len)) = tuple((
-        tag(INTERFACE_DESCRIPTION),
-        le_u32
-    ))(input)?;
+    let (rem, (_, block_len)) = tuple((tag(INTERFACE_DESCRIPTION), le_u32))(input)?;
 
-    take(block_len - header_len)(rem)
-        .map(|i| (i.0, Block::InterfaceDescription(InterfaceDescriptionBlock {
-            block_len
-        })))
+    take(block_len - header_len)(rem).map(|i| {
+        (
+            i.0,
+            Block::InterfaceDescription(InterfaceDescriptionBlock { block_len }),
+        )
+    })
 }
 
 pub struct EnhancedPacketBlock<'a> {
@@ -82,7 +71,7 @@ pub fn enhanced_packet_block(input: &[u8]) -> IResult<&[u8], Block> {
         le_u32,
         le_u32,
         le_u32,
-        le_u32
+        le_u32,
     ))(input)?;
 
     let (rem, packet_data) = take(captured_len)(rem)?;
@@ -91,9 +80,33 @@ pub fn enhanced_packet_block(input: &[u8]) -> IResult<&[u8], Block> {
     // seem to respect this
     //let packet_total_len = (captured_len + 3) / 4 * 4;
 
-    take(block_len - header_len - captured_len)(rem)
-        .map(|i| (i.0, Block::EnhancedPacket(EnhancedPacketBlock {
-            block_len,
-            packet_data,
-        })))
-}
\ No newline at end of file
+    take(block_len - header_len - captured_len)(rem).map(|i| {
+        (
+            i.0,
+            Block::EnhancedPacket(EnhancedPacketBlock {
+                block_len,
+                packet_data,
+            }),
+        )
+    })
+}
+
+pub fn extract_iex_data(input: &[u8]) -> IResult<&[u8], &[u8]> {
+    // Get the IEX payload out of each packet
+    // First step is the ethernet frame
+    let (rem, (_, _, _)) = tuple((take(6usize), take(6usize), tag([0x08, 0x00])))(input)?;
+
+    // Then the IP header
+    let header_words = rem[0] & 0x0F;
+    let header_len = header_words as u32 * 4;
+    let (udp_data, _header_data) = take(header_len)(rem)?;
+
+    // And finally, extract out of UDP
+    let (rem, (_, _, udp_len, _)) = tuple((be_u16, be_u16, be_u16, be_u16))(udp_data)?;
+
+    let udp_header_len = 8;
+    let (rem, iex_data) = take(udp_len - udp_header_len)(rem)?;
+    debug_assert!(rem.len() == 0);
+
+    Ok((rem, iex_data))
+}